(a) A square pile group of 9 piles passes through a recently filled u…

Question

(a) A square pile group of 9 piles passes through a recently filled up material of $4.5\text{ m}$ depth. The diameter of the pile is $30\text{ cm}$ and pile spacing is $90\text{ cm}$ centre to centre. If the unconfined compression strength of the cohesive material is $60\text{ kN/m}^2$ and unit weight is $15\text{ kN/m}^3$, compute the negative skin friction of the pile group.

(b) Distinguish between driven and bored piles. Explain why the settlement of a pile foundation (pile group) will be many times that of a single pile even though the load per pile on both cases is maintained the same.